• The KIPS Transactions:PartD
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• v.16D no.6
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• pp.835-844
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• 2009

Today, most of all the query processors in the world generally use the 'Pipelining' method to acquire fast response time (first record latency) and less memory usage. Each of the operator nodes in the Query Execution Plan (QEP) provides Open(), Next(), and Close() functions for their interface to facilitate the iterator mechanism. However, the embedded database systems for the mobile devices, based on the FLASH memory, usually require a function like Previous(), which returns the previous records from current position. It is because that, in the embedded environment, the mobile devices cannot fully provide it main memory to store all the query results. So, whenever needed the previously read records the user (program) should re-fetch the previous records using the Previous() function: the BACKWARD data fetch. In this paper, I introduce the 'Direction Switching Problem' caused by the Previous() function and suggest 'Block-wise Skipping' method to fully utilize the benefits of the block-based data transfer mechanism, which is widely accepted by most of the today's relational database management systems.

• Journal of IKEEE
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• v.17 no.2
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• pp.168-175
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• 2013

The delay times due to the propagating of data on PCB depend on the shape and length of interconnection lines when memory controllers and high speed memories are soldered on the PCB. The dependency on the placement and routing on the PCB requires redesign of I/O logic or reconfiguration of the memory controller after the delay time is measured if the controller is programmable. In this paper, we propose architecture of configuring logic for the delay time estimation by writing and reading test patterns while initializing the memories. The configuration logic writes test patterns to the memory and reads them by changing timing until the correct patterns are read. The timing information is stored and the configuration logic configures the memory controller at the end of initialization. The proposed method enables easy design of systems using PCB by solving the problem of the mismatching caused by the variation of placement and routing of components including memories and memory controllers. The proposed method can be applied to high speed SRAM, DRAM, and flash memory.

• Journal of Korea Water Resources Association
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• v.35 no.4 s.129
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• pp.411-423
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• 2002

Accurate and real time forecasting of runoff has a high priority in the drainage basins prone to short, high intensity rainfall events causing flash floods. To take into account the resolution of hydrological variables within a drainage basin, use of distributed system models is preferred. The Landsat Thematic Mapper(TM) observations enable detailed information on distribution of land cover and other related factors within a drainage basin and permit the use of distributed system models. This paper describes monitoring technique of rainfall excess by SCS curve number method. The time series maps of rainfall excess were generated for all the storm events to show the spatiotemporal distribution of rainfall excess within study basin. A combination of the time series maps of rainfall excess with a flow routing technique would simulate the flow hydrograph at the drainage basin outlet.

• Convergence Security Journal
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• v.12 no.3
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• pp.93-97
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• 2012

In this paper, we apply the next generation Internet TV solution, FLV has been designed and implemented. Currently being broadcast in the field to compress HD video in real time, as well as live Internet VOD services are available through the online system, the Internet LIVE broadcast and VOD service easy to operate and UCC services that support the solution. VOD video cameras and in real time using H264 CORECODEC to compress MPEC4, WMV, and real-time video streaming on the Internet, and phone system that supports the first, real-time recording of camera images featured nation's first real-time encoder system (Real time encoder system) is, Web and smart environment suitable for supporting the latest CORECODEC technology and software products. Second, the video can be played in MP4 player and customize your chat, and Custer (customizing) is a possible two-way Internet Broadcasting System. Third, CMS (Contents Management System) feature video content and course management content in real time via the Android phone and iPhone streaming service is available.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.5B
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• pp.386-394
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• 2008

Adoption of wireless communication facilities in mobile devices leads to increased vulnerability in individual privacy. One of such cases was discovered when a smart mobile phone of Paris Hilton at Oscar Award Ceremony was hacked a Swedish group of hackers. In this study, I wondered what sort of personal information could be exposed to hackers in such cases. In the course of survey, it was recognized that technical analysis of flash memory in mobile devices to check what kinds of data are stored there is technically almost impossible, since they are usually built in a proprietary manner. No generic tools could apply to discover their contents. Having recognized technical difficulties, it was inevitable to resort to a questionnaire survey to see awareness level with regard to personal privacy. We collected response from three hundred respondents by posting the questionnaire at World Survey on-line research site. What we have discovered was quite astonishing that even personal residence registration numbers have been found from nine of every ten respondents. Other data revealed include phone numbers, names, and personal bank accounts.

• Journal of Korean Society on Water Environment
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• v.37 no.6
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• pp.442-448
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• 2021

Seawater desalination is a technology through which salt and other constituents are removed from seawater to produce fresh water. While a significant amount of fresh water is produced, the desalination process is limited by the generation of concentrated brine with a higher salinity than seawater; this imposes environmental and economic problems. In this study, characteristics of seawater from three different locations in South Korea were analyzed to evaluate the feasibility of crystallization to seawater desalination. Organic and inorganic substances participating in crystal formation during concentration were identified. Then, prediction and economic feasibility analysis were conducted on the actual water flux and obtainable salt resources (i.e. Na2SO4) using membrane distillation and energy-saving crystallizer based on multi-stage flash (MSF-Cr). The seawater showed a rather low salinity (29.9~34.4 g/L) and different composition ratios depending on the location. At high concentrations, it was possible to observe the participation of dissolved organic matter and various ionic substances in crystalization. When crystallized, materials capable of forming various crystals are expected. However, it seems that different salt concentrations should be considered for each location. When the model developed using the Aspen Plus modular was applied in Korean seawater conditions, relatively high economic feasibility was confirmed in the MSF-Cr. The results of this study will help solve the environmental and economic problems of concentrated brine from seawater desalination.

• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.17-17
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• 1998

Synchrotron radiation is produced when charged particles moving with relativistic velocities a are accelerated - for example, deflected by the bending magnets which guide the electron or p positrons in circular accelerators or storage rings. By using special focusing magnetic lattices i in the particle accelerators it is possible to make the dimensions of the particle beam very small with a hi맹 charge density which results in a light source with high b디lIiance. Synchrotron light h has important properties which make it ideal for a wide range of investigations in surface s science. The fact that the spectrum of electromagnetic radiation emitted in a bending magnet e extends in a continuum from the 얹r infra red region to hard x-rays means that it is id않I for a v variety of spectroscopic studies. Since there are no convenient lasers, or other really bright l light sources, in the vacuum ultraviolet and soft x-ray re.밍ons the development of synchrotron r radiation has enabled enormous advances to be made in this di펌C비t spectr따 re밍on. P Polarization-dependent measurements, for ex없nple ellipsometry or circular dichroism studies a are possible because the radiation has a well-defined polarization - linear in the plane of orbit w with additional right-circular, or left-circular, components for emission an생es above, or below, t the horizontal, respectively. Since the synchrotron light is emitted from a bunch of charge c circulating in a ring the light is emitted with a well-defined time structure with a short flash of l light every time a bunch passes an exit port. The time structure depends on the size of the ring a and the number and sequence of filling of the bunches. A pulsed light source enables time¬r resolved studies to be performed which provide direct information on the lifetimes and decay m modes of excited states and in addition opens up the possibility of using time of flight t techniques for spectroscopic studies. The fact that synchrotron radiation is produced in a clean u ultrahi야 vacuum environment is of gr않t importance for surce science studies. The current t비rd generation synchrotron light sources provide exceptionally high baliance and stability a and open up possibilities for experiments which would have been inconceivable only a short time ago.

• Cartoon and Animation Studies
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• s.34
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• pp.23-43
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• 2014

The development of the Internet in the 21st century had made a variety of cross-cultural environment so that animations also have evolved with new features to Web-Animation. In Korea, the web-based flash animation leap forward to the animation Utopia in the early 2000's, but did not last long. The web-based animations should attract audience's attention not only with it's minimum streaming capacity but also with showing it's best qualities as well, Therefore, the stimulating narrative strategies were mandatories for web-animation in 2000's. The absence of in-depth research on media, poor revenue structure, and the emergence of mobile games and e-learning industries made the web-animation become just a one-time/one-consumable content. There were no subsequent generation of korean web-animation ever since. In this study, I want to introduce and analyze the american web animation series, (2005) as a new type of web-animation in current digital culture, In particular, I want to discuss how this web animation appeal to the audience with its narrative strategies through using some aspect of the internet culture which's differentiated from traditional media based cultures. This research could suggest diverse narrative strategies for the future web-animation with new vision. Moreover, This also allows to look at latest web-animation trends and its new experiments.

• Journal of the Korean Chemical Society
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• v.57 no.4
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• pp.432-438
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• 2013

We report a contact angle goniometer that can be easily assembled and used in high school and general chemistry experiments. It consists of an LED flash, a sample stand, and a camera fixed on an optical bread board, and the sample area is covered to block light from outside with a box with holes on both sides. ImageJ, free image analyzing software and a JAVA plugin (Drop_analysis) were used to determine the contact angle of liquid drop resting on solid surface. The contact angles of various liquids were successfully measured on various surfaces. The solid surface energies have also been determined using the Owen-Wendt method from the contact angles of $H_2O$ and $CH_2I_2$. The results reasonably agree with the previously reported values, showing the surface characteristics and modification as well as the dispersive and polar contributions. These contact angle goniometer and method for determination of the contact angle and surface energy can be applied to observation of various surface properties including wettability, hydrophilicity, and water repelling. Students can learn how the surface properties are related to the intermolecular interactions and gain experience about the equilibrium between the related forces, optics, and mathematical derivations.

• The KIPS Transactions:PartA
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• v.16A no.5
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• pp.357-368
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• 2009

Mobile IP storage has been proposed to overcome storage limitation in the flash memory and hard disks. It provides almost capacity-free space for mobile devices over wireless IP networks. However, battery lifetime of the mobile devices is reduced rapidly because of power consumption with continuous use of a WLAN device when multimedia contents are being streamed through the mobile IP storage. This paper proposes an energy-efficient WLAN device power control technique for streaming multimedia contents with the mobile IP storage. The proposed technique consists of a prefetch buffer input/output module, a WLAN device power control module, and a reconfigurable prefetch buffer module. Besides, it adaptively determines the size of the prefetch buffer according to a quality of the multimedia contents, and it dynamically controls the power mode of the WLAN device on the basis of power on-off operations while streaming the multimedia contents. We evaluate the performance of the proposed technique on a PXA270-based mobile device that employs the embedded linux 2.6.11, Intel iSCSI reference codes, and a WLAN device. Extensive experiments reveal that the proposed technique can save the energy consumption of the WLAN device up to 8.5 times with QVGA multimedia contents, as compared with no power control.